No need for Hayes to be playing anything above a 4C.
We don't know if he'll suck yet. It's one bad year, possibly under a coach he hated, in a situation he wasn't comfortable with.
The year before that 54 points, on an offensively inept team under Torts.
If anything I expect some improvement, because he's from Boston and Sully's gonna give him all the love/usage. That has a big impact on players' mental approach.
Eller for example felt valued here and improved on his prior year. You could tell in interviews that he was embracing the role. He liked that he got PP2 minutes.
Guys have random bouncebacks in their 30's all the time. Graves might be solid next year too. Nothing is certain.